Hack-saw frame



Jan. 15, 1929.

S. W. HALBERT HACK SA' FRAIB 7 Filed Jan. 18, 1927 r mvcmon 5A/B\10EL M HALBEBT ATTORNEY Patented Jan. 15, 1929.;

UNITED STATES 1,699,291 PATENT OFFICE".

SAMUEL W. HALBERT, OF LOS ANGELES, CALIFORNIA.

HACK-SAW FRAME.

Application filed January 18, 1927. Serial No. 161,873.

My invention relates to hack saws, and it has for a purpose the provision of a hack saw frame of telescopic form in order that it may be enlarged to accommodate a deeper cut when required.

It is also a purpose of my invention to provide a hack saw frame having simple and effective means for holding that end of the saw blade adjacent the handle of the frame in a manner to allow the frame to accommodate saw blades of various lengths or parts of broken blades.

A further purpose of my invention is the provision of a hack saw frame constructed of metal or other suitable material which is tubular in form to produce a frame of su perior rigidity and durability as compared to the flat forms of frames heretofore used.

I will describe only one form ofhack saw frame embodying my invention and will point out the novel 1 features thereof in claims.

In the accompanying drawings,

Figure 1 is a view showing in side elevation and partly in section one form of hack saw frame embodying my invention with a.

blade in applied position therein;

Figures 2, 3 and 4 are sectional views taken on the lines 2---2, 3-3 and 4-4, respectively, of Figure 1;

Figure 5 is a detail pers ective view of the blade holding bar embo ied in the frame shown in Figure 1.

Referring specifically to the drawings, my invention, in its present embodiment, comprises a U-shaped yoke tubular in cross sec tion, as illustrated in Figure 2, and including parallel arms 15 and 16 connected by an elongated intermediate portion 17. The arms 15 and 16 are adapted to be slidably received in sleeves 18 and 19, respectively, constituting heads and provided with means by which the ends of a saw blade 20 can be secured thereto. The association of the heads with the arms of the yoke is such that the arms are frictionally retained in longitudinally adjusted position within the heads, and by virtue of the telescopic connection it will be manifest that the yoke as a unit is capable of being extended outwardly or inwardly with respect to the heads in order that the depth of the frame as a whole can be varied as desired.

The sleeve head 18 has riveted to its lower or outer end a strip 21 shaped to form a sleeve 22 of rectangular form in cross sec tion, and in which is received the squared shank 23 of a bolt. This bolt is also provided with a threaded to receive a knurled nut 25, the latter providing means by which the bolt is adjusted longitudinally within the sleeve. The inner end of the bolt is provided with an ear 26 carrying apin '27 which is adapted to engage within the usual opening of one end of the saw blade 20. In this manner, the

saw blade is connected to the bolt, as will be understood.

The sleeve head 19 is formed by bending a single sheet of metal upon itself to provide companion members of such area and contour as to provide a handle 28 to which knurled and rounded strips 29 are secured to form a grip. These strips may be formed of bakelite or hard rubber, as desired. In order to facilitate manufacture the two sheets of metal constituting the sleeve 19 and the handle 28 may be formed integrally with a each other, as illustrated in the drawing,

and bent to form an elongated socket 30 at the lower edge thereof in which is received a blade holdingbar 31. This bar is constructed in the manner illustrated in Figure 5, in which its upper edge is formed at intervals with notches 32 and in any one of which a locking ke 33 is adapted to en age for securing the bar against longitu inal movement. The inner end of the bar is split and bent at right angles to provide a lip 34. This lip and the adjacent portion of the bar are formed with openings indicated at 35 in either of which may be extended a pin 36 for securing the other end of the blade 20 thereto. As the two portions of the bar are disposed at right angles to each other, it will be clear thatthe corresponding end of the blade 20 can be held in the same lane as that of the frame, as illustrated in Figure 1, or in a plane at right angles thereto when it is desired to position the blade with its cutting edge in a plane at right angles to the frame. It will, ofcourse, be understood that when holding the blade in the last mentioned position the bolt 23 can be removed from the sleeve 22 and turned ninety degrees, in order that its ear 26 will be disposed in a plane at right angles to the frame. Thus the other end of the blade 20 will be held in the same plane as the opposite end.

The locking key 33 comprises two blades of spiral form rotatable on a pintle 37 secured within and between the plates comrounded. shank 24 screw prising the head 19. A suitable opening 38 is provided in the plates in order to permit the necessary rotative movement of the key to cause one blade or the other to engage within any one of the notches 32 of the bar. By virtue of the spiral formation of the blades, it will be manifest that the key can be rotated to effect binding engagement of either blade within any one of the notches and to thereby firmly secure the bar against longitudinal movement within the sleeve 30. The adjustability of the bar 31 allows the frame to accommodate and securely hold blades of different lengths and, parts of broken blades, it being understood that the required tension of the blades can be secured by an adjustment of the nut 25.

In practice, the hacksaw is used in the usual manner to saw a piece of work, the yoke being pushed in on the heads 18 and 19 and held in such position bythe frictional engagement with the heads. As the cut increases in depth, the portion 17 of the yoke will move into engagement with the work and. thus be held against further tollowing the blade inwardly of the work, whereby the yoke will be extended from the heads as required to accommodate a deeper out. Of course, the yoke can be manually adjusted to enlarge the frame in the same manner as will be understood.

Although I have herein shown and described only one form of hack saw frame embodying my invention, it is to be understood that various changes and modifications may be made therein without departing from the spirit of the invention and the spirit and scope of the appended claims.

I claim as my invention:

1. A. hack saw frame comprising spaced heads, sleeves on the heads, saw blade ongaging members in the sleeves, means by which one of the members is adjustable to accommodate blades of dil'l erent lengths, means by which the other member is adj ustable to place the saw blade under tension, the first means including notches in the re spective member, and a key rotatable to engage within at least one of the notches for locking the member against movement lengthwise.

2. A hack saw frame comprising a pair of spaced tubular heads, one oi which is provided with a handle, a yoke of U form having its parallel portions slidably fitted in the heads to permit extension of the yoke, said heads having angularly disposed sleeves at one end, saw blade engaging members in the sleeves, means by which the member in the handled head is adjustable to accommodate blades of different lengths and comprising a plurality of notches in the member, and a key of spirally bladed form rotatably mounted in the handled head to engage within at least one of the notches for locking the member against lengthwise movement, and means by which the other member is adjustable to place the saw blade under tension.

SAMUEL HALBERT. 

